I have installed each bearing block flanges and carriage weldment onto the X axis rails…I did the bearing adjustments per instructions…when I did the jogging for the first time it locked up…like got stuck…most the of the bearing were tight ass hell on the X axis rails. Only way I could loosen these up was to loosen the big set screws that hold the flanges onto the carriage weldment. What might cause this? Its a big mess.
Thanks for your positive input
Loosen the cap screws that hold the adjustable bearing blocks on and back off the set screws. Then snug down the cap screws. Then turn the set screws until the bearings touch the rails. Then tighten the cap screws up. The carriages should roll with just a bit of hand pressure pushing them along.
I loosen the big set screws and then the adjusting set screws…the bearings are still tight as hell unless I loosen the big socketcap screws almost all the way…then one side wants to job before the otherside
I noticed that after the small setscrew is snug, that as the large screw is tightened pulling itself into a square position, it will move the bearing closer to the rail. This tends to make the small setscrew adjustment even tighter. really had to play around with too little or too much for a bit.
There will be tighter/looser spots along the rail also due to manufacturing tolerances being a little off here and there.
Just try and pick the best of both worlds while Checking Square between the torch mount and the slats OFTEN. That way you wont have to mess with it again. Good Luck. 
THIS IS THE RESPONSE I HAD GOTTEN FROM TECH SUPPORT
AFTER HAVING TO HAVE THEM EXPLAIN STEP ONE A COUPLE OF TIMES IT IS THE FOUR SCREWS AND NUTS THAT ARE ON THE GANTRY WHERE THE THREADED ROD GOES THROUGH…
LIKE YOURSELF I AM WONDERING WHY THINGS ARE NOT SQUARED UP ON BOTH SIDES…IS THIS A MANUFACTURING SCREW UP OR?
Advanced Tech Support (Langmuir Systems)
Aug 20, 2020, 2:52 PM PDT
Hello,
I have been asked to review this ticket. I designed this system and I have reviewed all of the pictures and I think i have a clear picture of what is going on. As you know the bearing block assemblies mount to a backing plate which is then mounted to the flange on the carriage. The mounting holes are greatly over-sized as compared to the corner fasteners that mate the flanges together. This gives the surface the X axis gantry tube mounts to some angular adjustability so that even if the Y axis Rail tubes are not exactly orthogonal to one another, the bearing blocks will not bind once the gantry is installed. For that reason, it is vital to not tighten screws that secure the bearing black assemblies to the Y axis carriage flanges until AFTER the gantry tube is installed and the preloads have been set.
Do the following to correct the issue:
- Disconnect the lead nuts so that the gantry can be manually cycled in the Y direction.
- Break loose but do not remove the 16 screws that secure the bearing block assemblies to the carriage flanges.
- Break loose the socket head cap screws that secure the adjustable bearing blocks. Back out the set screw a few turns each.
- At this point the gantry should move very freely with tons of lash in the system.
- Cinch down the socket head cap screws on the adjustable bearing blocks with minimal torque.
- Turn each of the set screws until at least one fixed bearing and both adjustable bearing blocks are touching the rail. Don’t overdue it here, you want minimum amount of preload necessary to ensure that there is not any free play and no more.
- Once step 6 is complete for all 8 adjustable bearing blocks, tighten the 16 screws that secure the bearing block assemblies to the carriage flanges.
If done correctly, the gantry should move back and forth with light hand pressure.
I have reviewed the spirit level pictures and everything appears to be acceptable. I am confident that once the process described is exactly followed, that the gantry will roll freely.
1 Like
Do you recommend this fix for when the lead screws are on? I’m a couple days into cutting and piling the lead screws won’t stop it from skipping.
My bearings are too tight and I need to re-adjust them but I’m wondering if having the whole table together means I can’t fix thme like what you mentioned above.